The invention relates to an apparatus for feeding fiber material, such as fiber flocks of cotton or the like, by means of a feeding duct to a processing machine, such as a carding machine. The apparatus is the type which feeds fiber material via a spiked feed roller to the feeding duct and removes it from the lower end by delivery rollers. The feeding operation is assisted by an air current which is evacuated through openings in the lower part of the duct walls. A change of width of the fiber material discharged from the duct may be provided by an adjusting member.
It has been known from U.S. Pat. No. 4,523,351 (German Pat. No. 31 49 965) that the working width for the fiber flock guidance is set by providing in the feeding duct at least one adjustable wall element adjustable at an angle from the side wall and obliquely pointing downwardly. In each angle position, the wall element is the hypotenuse of a triangle defined by the side wall of the duct and delivery rollers. Such as adjusting member entails difficulties in providing a uniform and homogeneous column of material in the feeding duct and of the delivery to the delivery rollers which affects the homogeneity of the fibrous web supplied to the processing machine.
Accordingly, an object of the invention is to provides a means for adjusting the width of a fiber flock web discharged from a feeding duct with homogeneous filling of the feeding duct so that, even with a modified width, a homogeneous fibrous web composed of the fiber flocks is positively discharged from the feeding duct.